National Research Institute of Tuberculosis and Lung Disease (NRITLD), Shahid Beheshti University of Medical Sciences, Tehran, Iran TANAFFOS (Respiration) 1735-0344 19 3 2020 07 01 Evaluation of the Effect of Caffeic Acid Phenethyl Ester (CAPE) on Pharmacological Responses of Isolated Rat Trachea in vitro 256 261 242695 EN Ali Asghar Hemmati Department of Pharmacology, School of Pharmacy and Physiology Research Centre, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran Mahin Dianat Department of Physiology, School of Medicine and Physiology Research Centre, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran Amir Jalali Department of Toxicology, School of Pharmacy and Toxicology Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran Department of Pharmacology and Toxicology, School of Pharmacy, Guilan University of Medical Sciences, Rasht, Iran Journal Article 2021 02 24 <strong>Background: </strong>Caffeic acid phenethyl ester (CAPE) is one of the major components of honeybee propolis and its structure is similar to flavonoids. CAPE has been shown to possess anti-inflammatory, immunomodulatory, and antioxidant properties. Despite a wide range of biological activities of CAPE, detailed biochemical mechanisms of its action are poorly described. The aim of the present study was to investigate the in vitro effect of CAPE on isolated rat trachea.<br /> <strong>Materials and Methods: </strong>A 20 mm long portion of rat tracheal spiral was submerged in 20 ml Krebs solution in an isolated organ bath at 37°C. Changes in tracheal contractility in response to the application of agonist agents were measured using an isometric transducer connected to a Harvard polygraph.<br /> <strong>Results: </strong>Acetylcholine (ACH), histamine (HIS), and CaCl2 caused the trachea to contract in a dose-dependent manner. Incubation of trachea with 10-7 M and 10-6M of CAPE induced a significant reduction in contraction induced by ACH and HIS. The degree of drug-induced tracheal contraction or relaxation was dose-dependent.<br /> <strong>Conclusion: </strong>The CAPE potential to relax the trachea may antagonize cholinergic and histaminergic receptors of the trachea. The findings provide new insight into the effectiveness of CAPE in the control of asthma and the possible use of propolis for its treatment. The results highlight the anti-muscarinic, anti-histaminic, anti-inflammatory, and relaxant activities of CAPE and critically show its potential therapeutic effects. https://www.tanaffosjournal.ir/article_242695_9f31eab4cfa10f96c0071635715b76b9.pdf